Wellington: New Zealand Prime Minister Jacinda Ardern gave birth to a daughter on Thursday and posted a message welcoming the healthy newborn "to our village."

She is the second elected world leader to give birth while holding office after late Pakistan Prime Minister Benazir Bhutto, who gave birth to daughter Bakhtawar in 1990.

In this photo released by the Office of the Prime Minister of New Zealand, Prime Minster Jacinda Ardern and her partner Clarke Gayford pose with their newborn daughter. AP

Ardern distributed a photo showing her and partner Clarke Gayford with the baby at Auckland City Hospital. The girl arrived at 4:45 pm weighing 3.3 kilogrammes (7.3 pounds).

"Welcome to our village wee one," Ardern wrote in the caption on Instagram. "Feeling very lucky to have a healthy baby girl."

She thanked everyone for their kindness and wishes. "We're all doing really well," she wrote.

Ardern's pregnancy has been followed around the world, with many hoping the 37-year-old will become a role model for combining motherhood with political leadership.

Former New Zealand Prime Minister Helen Clark said in an email to The Associated Press that it was a very happy day for Ardern and Gayford and that New Zealanders had taken the news of the pregnancy in their stride.

"This is a sign of our maturity as a country and its acceptance that combining career and family is a choice which women are free to make," she wrote. "Let's also celebrate Clarke as a modern man who is happy to be the full time parent of a young child."

The former prime minister said attitudes had changed since she'd entered politics and that was a good thing.

"For New Zealand, these events and the way our country has greeted them will be seen as inspirational by all who advocate for gender equality and women's empowerment," Clark wrote.

Jennifer Curtin, a professor of politics at the University of Auckland, said there was symbolic importance in Ardern giving birth, in that it showed political parties around the world that it was fine to have younger women as candidates.

She said women often tended to be older when they entered politics. She said in other fields, women have been combining motherhood and paid work for decades, but it has only recently become more manageable thanks to paid parental leave.

Deputy Prime Minister Winston Peters has taken over as acting prime minister. Ardern plans to take six weeks of leave before returning to work.

Under the arrangement, Ardern will still be consulted on major decisions, including issues of national security. She has said she's confident the government will continue to run smoothly in her absence.

She said that after the birth, she hoped to have some quiet time to enjoy as a family.

Asked earlier this month how the couple had been faring in their quest to choose a baby name, Ardern responded: "Terribly. Do you have any suggestions?"